1. Field of the Invention
This invention relates to a composition and a method for the treatment and stabilization of hazardous wastes so that they may be safely disposed or discarded in an environmental manner. Specifically, this invention relates to a composition and a method for the stabilization of hazardous radioactive wastes. Still more specifically, this invention relates to a composition and a method for the stabilization of low level radiation contaminated soil. Even more specifically, this invention relates to a composition and a method for encapsulating low level radiation contaminated soil so that said encapsulated soil may be safely disposed.
2. Description of the Prior Art
There are a host of hazardous waste materials that are difficult to dispose because of the possibility that they may contaminate the environment. These hazardous wastes include things like dioxins; polychlorobiphenyls; wastes containing heavy metals and the like; waste from sewage treatment plants; radioactive wastes such as that contained in contaminated soil or effluents from radiation producing plants and the like; and chemical wastes, among many others. As there are wastes generated by society, so there are processes described in the prior art that are said to either remove or stabilize these hazardous elements so that they can be safely disposed. Most of these processes are either too complicated to be economical or do not safely stabilize the hazardous wastes so that can safely be disposed environmentally.
It is said that hazardous waste products such as chemical precipitation sludges; waste ion exchange materials; metal cuttings, among others, can be stored in metal or plastic containers or mixed with a cement and then buried stored in the resulting cement container. Metal or plastic container storage is unsatisfactory since it is known that such containers can deteriorate with age and thus there is usually some leaking of the hazardous waste. Storage of hazardous waste materials embedded in cement has been somewhat successful but cement does not have good setting properties when mixed with most hazardous wastes. The containment of radioactive wastes within a cement matrix has also been reported. This too has been unsuccessful due to the poor mixing properties of cement and waste. Additionally, during the curing phase, the cement is known to form micro-channels and thus the radiation can leak through these channels into the environment.
It is also known to treat soil containing lead with a mixture of silicates. This process is said to effectively reduce the amount of detected lead in the soil by encapsulating the lead containing soil within a matrix of the silicate. Although this process has been tested successfully for lead in soil, it has not been used for the other commonly known wastes such as those listed above, in addition, considerable amounts of the silicate mixture must be used and this is costly.
Finally, it is also known to treat radioactive or toxic solid wastes with a polymerizable mixture of a styrene compound or mixtures of styrenes. It is said that large, solid blocks of this material are safe to handle and dispose. However, aging of this material is a problem and most styrene containing compounds are hazardous in and of themselves.